1. Field of the Invention
The present invention relates to a small, lightweight vacuum insulated switchgear with high reliability and performance and, more particularly, to a vacuum insulated switchgear that enables a busbar compartment and feeder compartments to be connected through insulated busbars.
2. Description of Related Art
In a power receiving facility, a closed electric panel (referred to below as a switchgear) is installed, which houses vacuum breakers for shutting down a current to a load or a fault current, disconnecting switches and earthing switches, which are used to ensure safety for operators who service and inspect the load, detecting units for detecting a system voltage and current, protective relays, and the like.
There are many methods of insulating switchgears of this type. Conventionally, air insulation panels and cubicle gas insulation switchgears (GISs), which use SF6 gas, have been used. Recently, a rapid shift to small components that use the solid insulation method, compressed air insulation method, and full vacuum insulation method is in progress in order to protect environments. To respond to this, a vacuum insulated switchgear has been suggested (in Patent Document 1, for example), in which double-break, three-position vacuum circuit breakers having breaking and disconnecting functions and earthing switches, which are vacuum insulated in the same way, are integrated by epoxy casting.    Patent Document 1: Japanese Patent Application Laid-open No. 2007-14086 (FIGS. 3 to 5)